Coil-retaining device



Aug. 28, 1956 H. H. ALLEN COIL-RETAINING DEVICE Filed March 17 1951 I H-HALLEN mlvsvra l wwmz iw FIG. 6.

United. States, Patent CGIL-RETAINING DEVIE Henry Hans Allen, London, England, assignor to British 'Celanese Limited, a corporation e f-Great Britain A lications [mu 11, 195-1, sedative. 216,242 :(ilalms priority, application Great Britain-.March 2.0} 1950 r Claim. (Cl; 242-416) This invention relates to a coilwetaining device intended foruse on a band wound in the=form of! a hollow coil.

In one form of apparatus for recording sound on an endless band, the band is employed wound in the form of a hollow coil with the innermost and outermost convolutions joined by a loop. When handling such a coil there is always the danger of the loop being drawn out so that the inner convolutions of the coil are so reduced in diameter that loading of the coil into the recording apparatus is difficult or impossible. Readjustment of the coil calls for considerable manipulative skill and is timeconsuming; There is, moreover, always the danger of the coil becoming so completely disorganized that the band must be broken, re-coiled and re-joined.

The present invention is concerned with a device which makes it possible to avoid these dangers when using such endless bands.

The device of the invention comprises a collar adapted to surround the convolutions of the coil at a point on the circumference of the coil with suificient clearance to permit free relative movement of the coil and the collar, and a clamp secured to said collar and movable into a position in which said clamp compresses the convolutions of the coil against the inside of the collar.

The collar may be made from metal, e. g. aluminium or an aluminium alloy, wood or rigid plastic, e. g. a composition having a basis of cellulose acetate, in sheet form by cutting, stamping or moulding.

The clamp is preferably in the form of a resilient cam pivotally mounted on the collar so that on being moved into clamping position it first compacts the convolutions of the coil against the inside of the collar and then presses the compacted convolutions against the inside of the collar by its own resilience. The resilient cam can be made of stout wire bent to a U shape, and having the limbs of the U bent out of the plane of the U to constitute a cam, the limbs of the U being adapted to engage the band near its edges. The collar can be an integrally closed ring, or it can be a rigid U-shaped member, the open end of the U being bridged by a rod upon which a suitably shaped resilient cam is pivoted. With the latter form of device the rod can be removable, e. g. threaded into one of the arms of the collar, so that the device can be assembled in place upon the coil.

In sound recording apparatus using endless bands of the type referred to the coil is mounted so that it can rotate as the band is drawn from the inside and returned to the outside of the coil. It has been found desirable, when using the device of the invention, to provide means for holding the device so that it cannot travel with the coil as the latter rotates. Such means may comprise, for instance, a clip adapted to grip a suitably shaped lug or other part of the device, or pegs between which the device rests.

By way of example three forms of coil-retaining device" in accordance with the present invention will now be described in greater detail with reference to the accompanying drawings in which:

ice.

Figure 1 is a front elevation and Figure 2 a side elevation, of one form of coil-retaining. device mounted. in fiiredposition on abracketwi'th its clamp in the. openposilti'on,

Figure 3 is anenlarged side elevation of the device of Figures 1 andi2', with the clamp in the closed position,

Figures 4. and 5" are a front elevation'an'd a side elevation respectively of a second form of coil-retaining. de. vice; and

Figures .6' and 7 are a front elevation and side elevation of a third form of coil-retaining, device.

The device shownin Figures l3"comprises a. rectangular collar 1 cut from a sheet of cellulose acetate, pro.- vided with a lug '2 depending from its lower ed gcn the lug having a slot 3' for securing it in position on a bracket 4 by means of a screw 51 The convolutions 6 of 'a coil of film pass through the collar 1 which provides ample room for their free longitudinal movement. The lug 2 is bored with lateral holes 7 in which is pivotally mounted a clamp ing member 8 formed by first bending springy brass wire of No. 16 standard wire gauge to a U-shape, and then bending it out of the plane of the U to the shape shown in Figures 2 and 3. The ends of the wire 9 are bent inwards and enter the holes 7 in the lug 2. In order to enter the film 6 in the collar 1, the side of the collar may be split, as indicated at 12, and the split may be afterwards closed by means of a solvent (e. g. acetone) or other adhesive. Alternatively the film 6 may be threaded through the collar 1 before having its ends joined to make a closed coil.

In Figure 2 the clamping member 8 is shown swung clear of the opening of the collar 1, but in the enlarged view of Figure 3 the clamping member is shown in the clamping position, where its upper portion 10 urges the convolutions 6 of the film upwards into engagement with the inner top surface 11 of the collar 1, the portion 10 engaging the convolutions 6 near the edges thereof so as to avoid frictional engagement with the main central area of the inner side of the film. When the clamping member 8 is turned into the position shown in full line in Figure 3, it is distorted by its engagement against the surface 11 by the resilience of the wire of which the member 8 is made. The dotted lines in the Figure 3 show the undistorted form of the member 8 for the purposes of comparison.

In Figures 4 and 5 the collar comprises a U-shaped member 14 similar to the collar 1 without the upper side thereof. The upper side of the member 14 is closed by means of a pin 15 passing through a tube 16 disposed between the limbs of the member 14 and having a hexagonal head 17 at one end and a pair of nuts 18 at the other. The clamping member 19 is formed as in Figures l-3, of springy brass wire, bent to a U-shape and then distorted out of the plane of the U. The ends of the wire are formed into loops 20 through which the pin 15 passes. The member 19 is shown in the open position in full lines in Figures 4 and 5, and in the closed position in dotted lines in Figure 5. The member 19 is arranged to clamp the convolutions of a band enclosed by the U-shaped member 14 and pin 15, against the lower inner surface 21 of the member 14. The portions 22 of the member 19, extending across the limbs of the member 14, limit the motion of the member 19 in both directions.

The device shown in Figures 6 and 7 comprises a U-shaped member 14 similar to that of Figures 4 and 5. The clamping member 23 is formed of springy sheet brass, one edge of which is rolled to form a tube 24 through which passes a pin 25 closing the limbs of the U-shaped member 14. The clamping member is bent to the shape shown in Figure 7 and its free edge is rolled to form a head 26. Unlike the clamping members 8 and 19 of Figures 1-5, the member 23 engages the film across its whole width. In Figures 4-6 the film can be entered in the device by removing the pin 15 or 25 and clamping member 19 or 23.

Having described my invention, what I desire to secure by Letters Patent is: x

1 As a recording element for a sound-recording apparatus, the combination of a band'of recording medium wound inthe form of a hollow coil having the innermost and outermost convolutions joined by a loop, with an integrally closed ring adapted to surround the convolutions of said coil, at a point on the circumference of said 'coil, with sufiicient clearance to permit free relative movement of said coil and said' ring, a shaped lug having lateral holes extending into its sides integral with said ring for mounting the recording element in a fixed position on the sound recording apparatus, and a resilient cam made of springy Wire having its free ends bent inwards and engaging the lateral holes in said lug for pivotally supporting said cam on 'said ring, and being bent to a U-shape and having the limbs of the U bent out of the plane of the U to constitute a cam, the limbs of the U being adapted to engage the band near its edges and to compress the convolutions of said coil against the inside of said ring by the resilience of said wire.

5 References Cited in the file of this patent UNITED STATES PATENTS 844,540 Roy et al. Feb. 19, 1907 1,064,932 Rode June 17, 1913 1,087,065 Kaiser Feb. 10, 1914 1,205,524 Flatow Nov. 21, 1916 1,991,394 Klein Feb. 19, 1935 2,021,374 Pagenkopf Nov. 19, 1935 2,311,383 Hardenberg Feb. 16, 1943 2,327,108 Heyer Aug. 17, 1943 2,398,639 Heyer Apr. 16, 1946 2,559,822 Kelly July 10, 1951 FOREIGN PATENTS 24,803 Austria July 10, 1906 208,726 Great Britain May 29, 1924 

